JPH0720450Y2 - Lip seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of a lip-type seal for sealing the circumference of a rotating shaft.

[Conventional technology]

2. Description of the Related Art Conventionally, as a shaft sealing device used in, for example, a car cooler compressor, there is a lip type seal as shown in FIG.

This lip-type seal includes a rubber-made lip member 1 on the sealed space A side in the compressor, a synthetic resin (PTFE or the like) lip member 2 on the anti-sealed space B (atmosphere) side, and the synthetic resin lip member 2 It is composed of a metal backup ring 3 on the side opposite to the hermetically sealed space B and a metal outer case 4 in which the outer diameter portions of these members 1, 2, 3 are caulked and fixed. The base portion 101 of the rubber-made lip member 1 which is airtightly fitted to the inner circumference of the outer case 4 extends in the axial direction and toward the sealed space A side, and the rubber-made lip member 1 including the base portion 101.
By embedding a metal ring 103 having an L-shaped cross section in the outer diameter portion 102, the respective members 1, 2, 3 are stably fixed.

This lip-type seal is airtightly mounted on the inner peripheral surface 7 of the housing of the compressor in the metal case 4 via the O-ring 5, and the step portion 7a of the inner peripheral surface 7 is provided.
And the lip ring 1, which is fixed between the snap ring 6 fitted in the annular groove of the inner peripheral surface 7 and extends toward the sealed space A side.
The inner diameter sliding surfaces 1a, 2a of 2 are in sliding contact with the outer peripheral surface of the shaft 8 inserted into the housing, and prevent refrigerant (Freon) and refrigerating machine oil in the sealed space A from leaking to the atmosphere B side. .

[Problems to be solved by the device]

However, according to the above-mentioned conventional lip-type seal, the metal ring 103 embedded in the outer diameter portion 102 of the rubber-made lip member 1 has a small adhesive force with the surrounding rubber material due to slight variations in the vulcanization molding process. When the sealed fluid has a large amount of permeation into the rubber material such as Freon, the swelling of the rubber material causes peeling of the adhesive surface from the metal ring 103 as shown in FIG. In this case, further changes in conditions such as temperature and pressure may cause expansion of freon or the like that has entered the peeled portion C, causing a foaming phenomenon or cracks, leading to destruction of the lip member 1. there were.

In view of the above, the lip-type seal of the present invention has been made in view of obtaining stable sealing performance for a long period of time.

[Means for Solving the Problems]

In order to solve the above problems, the present invention provides a lip-type seal in which an axially formed base formed on the outer diameter of a rubber lip member and extending toward the sealed space is airtightly fixed to the inner circumference of an outer case. In the surface of the outer peripheral portion of the rubber lip member including the base portion facing the sealed space, an outer diameter flange portion press-contacted to an end surface of the base portion on the sealed space side, and an inner circumference of the base portion. A caulking portion at the end of the outer case is additionally provided with a pressing plate including an axial portion that comes into pressure contact with a surface and an inner diameter flange portion that comes into pressure contact with the outer diameter portion of the rubber lip member on the inner peripheral side of the base portion. It was fixed by.

[Action]

In the lip-type seal of the present invention, the holding plate attached to the surface facing the sealed space in the outer diameter portion of the rubber-made lip member is stable in place of the conventional embedded metal ring instead of the embedded metal ring. The axial portion of the holding plate clamps the axially extending base portion of the lip member in a compressed state with the outer case, and the outer diameter flange portion has the axial direction. Of the rubber member on the inner diameter side of the base portion to the anti-sealing space side while preventing the escape deformation of the base portion that is compressed in the radial direction between the base portion and the outer case in the axial direction. It is pressed to suppress deformation of the lip member toward the sealed space during vacuum.

〔Example〕

The present invention will be described below with reference to an embodiment shown in FIG. The same parts as those of the conventional structure described above are designated by the same reference numerals, and the description thereof will be omitted.

In the lip-type seal of the present embodiment, the rubber-made lip member 1 is fitted on the inner peripheral surface of the outer case 4 by a base portion 9 that extends from the outer diameter in the axial direction toward the sealed space A, and includes this base portion 9. The outer diameter portion 10 has surfaces 11, 1 facing the sealed space A side.
A pressing plate 14 composed of an outer diameter flange portion 15, an axial portion 16 and an inner diameter flange portion 17 extending along 2, 13 is additionally provided. More specifically, the holding plate 14 is an outer diameter flange portion.
The outer casing 4 is fixed by a caulking portion 4a at the end portion of the outer case 4, and is pressed against the end surface 11 of the base portion 9 on the sealed space A side. The base portion 9 is sandwiched between the inner peripheral surface of the case 4 and the inner peripheral surface of the case 4 by an appropriate tightening margin, and is pressed against a surface 13 of the inner diameter flange portion 17 continuing to the inner diameter side of the base portion 9 toward the synthetic resin lip member 2 side. It is pressing.

Therefore, according to this structure, since the pressing plate 14 presses and fixes the outer diameter portion 10 of the rubber-made lip member 1 from the sealed space A side, adhesion peeling due to swelling cannot occur, and the rubber material is not formed. The lip member 1 made is extremely stable.

[Effect of device]

As described above, according to the present invention, the peeling of the adhesive due to the swelling and the foaming or cracking due to the peeling, which is caused when the metal ring is embedded and bonded to the outer diameter portion of the rubber lip member, and the rubber lip is not formed. Since the member is fixed very stably, stable sealing performance can be maintained for a long period of time.

[Brief description of drawings]

FIG. 1 is a half cut sectional view showing an embodiment of the present invention, FIG. 2 is a half cut sectional view showing an example of a conventional structure, and FIG. 3 is an explanatory view of a state where peeling has occurred. 1 rubber lip member, 4 outer case 9 base part, 10 outer diameter part 11,12,13 surface facing sealed space side 14 retainer plate, 15,17 flange part 16 axial direction part, A sealed space

Claims (1)

[Scope of utility model registration request] 1. A lip-type seal in which a base portion formed on the outer diameter of a rubber-made lip member and extending in the axial direction and toward the sealed space is airtightly fixed to the inner circumference of an outer case, the base portion including the base portion. An outer diameter flange portion of the outer surface of the rubber lip member facing the sealed space, which is in pressure contact with an end surface of the base portion on the sealed space side, and an axial direction which is in pressure contact with the inner peripheral surface of the base portion. Section, and an inner diameter flange section that comes into pressure contact with the outer diameter section of the rubber-made lip member on the inner peripheral side of the base section, and is attached by a caulking section at the end of the outer case. A lip type seal characterized by